CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

• Published in: PLOS Neglected Tropical Diseases
• Main Authors: Andréia Manso de Matos, Karina Inacio Carvalho, Daniela Santoro Rosa, Lucy Santos Villas-Boas, Wanessa Cardoso da Silva, Célia Luiza de Lima Rodrigues, Olímpia Massae Nakasone Peel Furtado Oliveira, José Eduardo Levi, Evaldo Stanislau Affonso Araújo, Claudio Sergio Pannuti, Expedito José Albuquerque Luna, Esper George Kallas
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2015
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270; Arctic
• Online Access: https://doi.org/10.1371/journal.pntd.0003520; https://doaj.org/article/3b71de0fe78846d18697dcc92639cd80

Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population.